Ziggy,
If your secretary has worked hundreds of hours on this, it would be a terrible shame for all that work to go to waste. You have given warnings, why not now issue the Notices to Comply? It seems you will not get the miscreant’s attention until this step is taken, and it may yield the desired results.
If the miscreant continues in defiance, then hopefully all the groundwork done by your secretary will provide context and evidence for orders at NCAT.